Additional parts complete latest key acquisition; NCX-500 hits the ether …

Friday, Sept. 18, 2020

A couple of days ago I got into my bin of Vibroplex parts and located the parts I needed to make my recently acquired Sienna Brown Vibroplex Champion a complete key.

I don’t know that I have seen another Sienna Brown Champion, seems like the most common brown-based key I’ve seen pictured over the years is the Original or the Lightning Bug.

The key is serial number 387,626, dates to 1979, the year Vibroplex was purchased and moved from New York to Maine. The Champion and Lightning Bug models were discontinued soon afterwards.

I purchased a finger and thumb piece from eBay seller Radio Junkyard. The pieces are 3D printed, and they were less expensive that the parts via Vibroplex. The parts have a textured finish, which is touted as a “non-slip” finish. I’ve never had an issue with my finger or thumb slipping while operating a bug. I suspect that 3D printing them with a smooth finish is probably beyond the capabilities of current 3D printing technology — either than or cost prohibitive. Either way, the finish was NOT an issue. They parts arrived and most importantly, fit perfectly. The seller even included the small screw for the thumb piece.

1979 Sienna Brown Vibroplex Champion SN 387,626.

So how’s it play? So far, so good. I haven’t had a chance to try it on the air yet, but I suspect it’ll be as good as the rest of my Vibroplex bugs.

NCX-500 ON-THE-AIR. This evening I put my recently unearthed National NCX-500 on the air to check into my Georgia CW traffic net.

Because the 500 has more than 1,100 volts on the finals, National emphasizes that you don’t hold the key down long while tuning, lest you’ll blow the finals. The radio uses a pair of sweep tubes, inexpensive tubes “back in the day” but rather pricey today as a matched set.

The NCX-500 was a rig designed to compete with the likes of the Yaesu FTDX 400, and other HF rigs of the day that posted input powers of more than 300 watts. SSB ruled the day, and CW was little more than an afterthought with the NCX-500, much as it was with the Hallicrafters SR-150.

My new sienna brown Vibroplex Champion in front of my National NCX-500 HF transceiver. I didn’t have time to cobble together a cable to match the NCX-500, I had to use a straight key — in this case, the key was a Nye Viking Master Key. I originally hated the feel of the Master Key, but I’ve come to appreciate how smoothly it operates.

The NCX-500 has a crappy sidetone; it also lacks any kind of CW filtering. When you switch to CW, you hear the same 3KC bandwidth as you do on SSB. Ugh! Fortunately tonight there were no other signals in the bandpass.

The NCX-500 also lacks semi break-in or break-in keying on CW; probably because it also lacks VOX. The Swan rigs of the day also lacked VOX; it was an add-on optional accessory. Working CW, to transmit you have to flip the MOX button, which mutes the receiver until you flip it back at the end of the transmission. I had to try to flip the MOX switch as quickly as I could and I still missed the first couple of characters from the NCS. Go figure.

Despite all the “deficits,” the rig did a fine job. I tuned the rig for about 100 watts output, which seemed to be about the max. I looked at the manual, and there were notes from the last time the radio was serviced, in 1983. New finals were installed, and the rig was aligned.

I’m considering listing the rig and power supply separately. The shipping for the AC-500 power supply is going to be high, plus trying to securely pack the thing.

I’m going to pack the NCX-500 like the seller did who I bought it from in 2004 — he took the cover off and packed bubble wrap in the rig to help secure the tubes.

The seller had the rig and power supply wrapped in bubble wrap, and individually boxed. The larger box had the boxes packed solidly, and his good packing is why there was no damage to the gear. The damn box was a heavy son of a bitch; I would have hated to have been the UPS man who delivered it.

The power supply is supposed to be 21 pounds; maybe its because its a very dense package, but it felt closer to 40 pounds.

I need to pull the cover and get pics of the chassis and rear of the rig. Its quite a clean example of an NCX-500. Probably should do the same with the NCX-200, its just about as clean a rig as the 500.

73 es CUL … de KY4Z …. SK … SK …. (dit dit) ….